Mercedes-Benz will be presenting its first electric vehicle with Range Extender at the 2011 Frankfurt International Motor Show in the guise of the Concept B-Class E-CELL PLUS. The combination of electric drive and petrol engine ensures excellent suitability for both everyday use and long journeys. The energy accumulator takes the form of a lithium-ion battery from Deutsche Accumotive, which enables local emission-free driving up to a range of 100 kilometres. Thanks to the additional three-cylinder petrol engine, the Concept B-Class E-CELL PLUS has a total range of up to 600 km. The concept vehicle presented at the 2011 Frankfurt International Motor Show provides a foretaste of the series which is to go into production in 2014. The Concept B-Class E-CELL PLUS adds an all-purpose battery-powered vehicle with Range Extender to Mercedes-Benz's range of electric vehicles.

A new addition to Mercedes-Benz's portfolio of electric cars is the near-series Concept B-Class E-CELL PLUS – a compact model that meets all the needs of daily motoring with a total range of up to 600 kilometres. As such, this electric vehicle is also ideally suited to long journeys and offers its driver unrestricted mobility. This is made possible by the combination of a powerful electric drive generating a peak power output of 100 kW and a continuous output of 70 kW with a 50 kW petrol engine. The latter performs a dual role: at low vehicle speeds it charges the battery via a generator. At higher speeds – on prolonged motorway stretches, for example – it additionally serves as a driving engine, acting on the front wheels together with the electric motor via a newly developed automatic transmission.

In all-electric, local emission-free mode the Concept B-Class E-CELL PLUS has a range of up to 100 kilometres. This covers over 80 percent of daily driving needs. The total range of up to 600 kilometres allows the vehicle to be used for long journeys, too. This means that the electric vehicle with Range Extender is fully suitable for everyday use and can be relied upon to reach its destination, even with a fully discharged battery. In combined driving mode the vehicle emits 32 grams of CO2 per kilometre.

"The Concept B-Class E-CELL PLUS shows that our new range of compact cars is all set for the future. The variant involving a battery-electric vehicle with Range Extender further broadens the range of alternative drive concepts from Mercedes-Benz," notes Prof Dr Thomas Weber, Member of the Board of Management at Daimler AG, responsible for Group Research and Mercedes-Benz Cars Development. "This innovative and highly flexible concept meets our customers' wish for emission-free driving coupled with a large range."

The vehicle concept – the best of two worlds

The Concept B-Class E-CELL PLUS is an electric vehicle meeting all daily motoring needs which combines the best of two worlds: all-electric driving and driving with a tried and tested high-tech combustion engine. This combination allows long journeys which to date have been the reserve of vehicles powered by a combustion engine alone or electric cars fitted with a fuel cell. The two drive units are extremely compact and are accommodated in the engine compartment at the front together with the transmission and the generator. The powerful lithium-ion battery and the fuel tank are located in a false floor at the rear – the so-called "Energy Space" – which has been developed specially for alternative drives. For other drive variants it is also possible to install gas or hydrogen tanks here, for example.

Intelligent control of the drive system for unrestricted mobility

The intelligent electronic control system of the Concept B-Class E-CELL PLUS ensures perfect handling in every driving situation. Activation and deactivation of the combustion engine take place fully automatically and go unnoticed by the driver. Electric motor and combustion engine work so intelligently together that the drive unit is able to select the most fuel-efficient mode in every driving situation in a fraction of a second – from stop and go in the city to speedy driving on the open road. With the Concept B-Class E-CELL PLUS there are basically two operating modes, depending on the battery charge status:

When the battery possesses sufficient energy, the vehicle runs locally emission-free on electric power alone. The energy accumulator can be recharged by means of a conventional domestic power socket. Rapid charging is also possible with this vehicle. This enables a charging time in the order of one hour.

When the battery charge status drops below a certain limit, the combustion engine is activated ("Range Extender mode"). The large range which is available in "Range Extender mode" ensures that the vehicle will always reach its destination, even if the battery is flat. Acceleration from 0 to 100 km/h in approx. 11 seconds and the top speed of 150 km/h are both attainable in either operating mode. In order to ensure the most efficient possible motoring, two variants are possible, depending on the vehicle's speed:

Below a speed of around 60 km/h, the combustion engine and generator attend to on-board power generation ("serial mode"). In this case, the combustion engine is run in the most fuel-efficient mode.

At speeds of over 60 km/h the combustion engine acts as a driving engine together with the electric motor ("parallel mode"), transmitting the generated power to the front axle. Any excess power generated by the combustion engine is used to charge the battery and to run the ancillary units.

Highly efficient lithium-ion battery with long service life

The energy accumulator is accommodated in a false floor system at the rear of the vehicle – the so-called "Energy Space" – which has been developed by Mercedes-Benz specifically for alternative drives. The energy accumulator employed here is a particularly powerful state-of-the-art lithium-ion battery designed specifically for automotive applications. It is produced by Deutsche Accumotive GmbH & Co. KG, a joint venture of Daimler and Evonik.

The battery can be charged using any standard domestic power outlet or at a public charging station, by means of the charge socket integrated in the rear bumper and the 3.3 kW on-board charger.

When the car goes into production, convenient remote checking and remote configuration of the vehicle will be possible by means of the so-called Vehicle Homepage. The driver will be able to access his vehicle via the internet, using his PC or smartphone. In this way, it will be possible to check the current charge status of the lithium-ion battery or to verify the vehicle's current range on a map. A further feature is smart charging. This involves the customer selecting a desired time for the beginning of his journey. The system then ensures that the battery is fully charged and, if desired, that the vehicle is air‑conditioned at this point in time. The facilities offered by the Vehicle Homepage are rounded off by further convenience functions, such as a route planner designed specifically for electric vehicles.

Comfort and safety to the highest standard

In terms of safety and comfort, the Concept B-Class E-CELL PLUS meets Mercedes-Benz's high standards in every respect. The vehicle combines compact exterior dimensions with a spacious and variable interior and luggage compartment. Five full-size seats make it an all-round electric car for the family, leisure and general motoring. The new electromechanical steering and enhanced driving dynamics provide for refined sportiness in the field of electric mobility. A striking feature of the Concept B-Class is the copper-coloured linear graphic design which accentuates the vehicle and lends it a dynamic appearance. High-quality black nappa leather and copper-coloured double lap seams have been used in the interior.

The concept vehicle is a match for its siblings when it comes to active and passive safety features, too. Like all models of the new compact car generation, the Concept B-Class E-CELL PLUS also comes with COLLISION PREVENTION ASSIST, a new assistance system which will help to avoid rear-end collisions in future. In keeping with the ongoing democratisation of safety, the B-Class E‑CELL PLUS will also feature a number of additional assistance systems adopted from the larger model series.

These include:

Adaptive Highbeam Assist

Blind Spot Assist and Lane Keeping Assist

Attention Assist (standard)

Speed Limit Assist (speed limit sign recognition)

Active Parking Assist

Brake HOLD function (standard with 7G-DCT)

Hill Hold function

LINGUATRONIC

Reversing camera

PRE-SAFE® (featuring for the first time in this class of vehicle)

As such, the Concept B-Class E-CELL PLUS sets new standards in the areas of compact electric vehicles with regard to comfort, safety and agility.